Accumulating empirical evidence (e.g., Hoge et al., 2004) documents that a significant minority of soldiers returning from Operation Iraqi Freedom report clinically significant levels of PTSD symptoms and associated impairment. Only a minority of the symptomatic receive any formal mental health treatment in the months following redeployment, however, opening the door to chronic PTSD. When symptomatic soldiers are asked about treatment, they identify the stigma associated with mental illness and the potential impact of seeking treatment on their military career (should it become known to the chain of command) as important reasons not to seek care. These facts, combined with empirical evidence documenting that redeployed soldiers who are symptomatic upon return typically remain symptomatic for at least the first year after redeployment, point to a pressing need for evidence-based early interventions that assist service members to help themselves manage and reduce PTSD symptoms at their own pace, on their own terms. In this application, we describe our plans for conducting a randomized field trial of a promising, Internet based, resource-efficient, self-training intervention aimed at reducing PTSD symptomatology and associated functional impairment among combat-exposed soldiers. The intervention is designed to be both efficacious in reducing PTSD symptomatology and attractive to soldiers returning from combat who are experiencing PTSD symptoms, but fear seeking formal mental health treatment because of the stigma and the perceived negative career impact. The intervention combines aspects of both stress inoculation training and cognitive behavioral therapy, and our goals for it include: (1) producing clinically-significant reductions in participants' PTSD symptomatology, (2) increasing their understanding of the benefits of formal treatment, and (3) creating more positive attitudes toward it. [unreadable] [unreadable] [unreadable]